<!DOCTYPE html>
<html>
<head>
    <title></title>
</head>
<body>
    <script>
        var b = true;
        var b = new Boolean();
        var b = new Boolean(-99);

        var b = Boolean();
        var b = Boolean(-10);
        var b = Boolean('');
        var b = Boolean(0);
        var b = Boolean(null);
        var b = Boolean(undefined);
        var b = Boolean([]);

        console.log(b);
        console.log(typeof b);
        console.log(b.constructor);
        
    </script>
</body>
</html>